1. Field of the Invention
This invention relates to deadbolt type lockset assemblies. More particularly, this invention relates to a deadbolt type lockset in which one of two different backset distances may be selected prior to assembling the lockset in a door.
Deadbolt locksets typically are provided with one of two different backsets. The backset is the distance from the edge of the door to the actuating knob axis. The most common backset distances are 23/8" and 23/4". In a new door, the customer must prepare the door by drilling for specific backset dimensions. In the replacement market, doors are already drilled and the customer must obtain a proper backset deadbolt lockset to match the pre-drilled door.
2. Description of the Prior Art
In the prior art, one of two completely separate deadbolt locksets were provided depending upon the desired backset. Several problems arise due to the use of separate deadbolt locksets. In the new construction market, the wrong backset may be specified by the customer or packaging and shipping errors may occur. The result in either case is that the customer will receive the wrong deadbolt for his project. In the retail market, there are a large number of products returned when the customer discovers that an error was made in the selection of a deadbolt for his application. Such errors result in a variety of losses after the seal of the package has been broken. Furthermore, the provision of two different deadbolt locksets creates problems of inventory maintenance.
U.S. Pat. No. 4,372,594 to Gater discloses a deadbolt lockset which can be adjusted to provide either a 23/8" or a 23/4" backset distance. The lockset includes a telescopic deadbolt connected to a deadbolt actuating mechanism. Without adjusting the deadbolt actuating mechanism, the deadbolt can be lengthened or shortened to provide the desired backset distance.
Copending U.S. patent application Ser. No. 485,180, filed Apr. 18, 1983 and assigned to TRE Corporation, discloses a spring latch-type lockset also having a selectable backset distance.